Sharapova’s 15-month suspension for taking the cardiac drug meldonium ends on April 25 and the Russian will play her first match the following day, having been handed a wildcard to the Porsche Grand Prix in Stuttgart.

Her participation in the event has proved controversial because the tournament in fact begins two days before her ban runs out. However Sharapova, who is also sponsored by Porsche, has been guaranteed a delayed Wednesday first-round match to ensure her participation.

Sharapova, 29, has also been given wildcards into the Madrid Open and the Rome Open, which are both ranked as WTA Premier Tournaments. This means that should she perform strongly she will likely be ranked back in the top 100 in time for Wimbledon, the third grand slam of the season.

This has left many players on the tour disgruntled – including Watson.

Watson has thrown herself into the debate (Getty)

Speaking after her first round exit from the Miami Open, the 24-year-old acknowledged that Sharapova’s commercial draw is impossible to deny, but claimed that the wildcards she had been presented with were dubious “from a moral standpoint”.

“From the tournament standpoint, she will bring in the crowds and make money,” said Watson. “But, from a moral standpoint, you should have to work your way back up if you've been on a ban. It just seems a bit easy.”

Watson is not the only player on the WTA Tour to express the opinion that Sharapova is being handed an easy ride back to the top of the sport, with former world number one Caroline Wozniacki claiming the Russian’s Porsche Grand Prix wildcard was “disrespectful” to other players.

"Obviously rules are twisted and turned in favour of who wants to do what," said Wozniacki, who lost the last match between the two in 2015.

"I think everyone deserves a second chance... but at the same time, I feel like when a player is banned for drugs, I think that someone should start from the bottom and fight their way back.”

The current world number four, Dominika Cibulková, is another to have publicly criticised the decision, stressing that the sport should maintain a zero-policy approach when it comes to doping, a stance also vigorously supported by Andy Murray.

Cibulková is another to question Sharapova's comeback (Getty)

“I don’t think it is right but what can we do about it? She’s still banned but she can come on site on Wednesday, that’s pretty strange,” Cibulkova said in Miami.

“For me it’s not okay and I spoke to some other players and nobody is okay with it, but it’s not up to us.

“All the people who are taking care of these things should know the rule and do the right thing. It’s not about her, but everyone who was doping should start from zero.”

The Russian could yet appear at this year's French Open (Getty)

Sharapova has kept a low profile throughout the growing controversy, although Steve Simon, chief executive of the WTA Tour, defended the manner of her return to the sport.

“There are many instances when the player is not at the tournament until the night before or the morning of the match based upon where they are travelling from, so that is not a factor,” he said.

“They have to be available for their match in the first round. If Maria' s suspension had ended on the Thursday she wouldn't have been able to play, period. Traditionally this tournament plays its first round over three days.”